Ridge ventilation apparatuses conventionally used, generally include a structure in which ridge ventilators are projected above ridge tiles. Therefore, since the ventilators are formed separately above ridge tiles, their shape does not match that of the roof. In addition, since end caps are necessary for enclosing the ends of the ventilators, and since it is not easy to shape the form of the caps so as to correspond exactly to that of the ventilator's end, there often occurs a situation in which the caps do not seal the ventilators sufficiently.